The disclosure relates generally to data storage systems, and more particularly to archiving and restoring data in a storage system.
Users of data storage disk systems often offload or archive less frequently used data to tape storage systems as tape systems provide far larger capacity and lower cost per data unit. When the users need to access the archived data again, a tape archive library system mounts the tape cartridges containing the archived data into the system and restores the archived data from the tape cartridges. Such a tape archiving process may lead to a delay in accessing the desired data as the data is not readily available in disk storage when it is needed.
As the cost of disk storage per data unit continues to decrease, disk storage is becoming an attractive medium for data archiving. Current data archiving solutions using disks often have a substantial amount of metadata associated with data compression and uncompression, which impacts system performance. In addition, metadata adds complexity to the implementation of storage management functions in the system.
“Remote copy” is another technology that may be used for archiving by replicating data at a remote storage facility. Remote copying transfers data from the main or local storage facility to the remote storage facility each time data is written or updated to a storage device of the local facility. However, remote copy, as well as implementations of backup and restore technologies introduce additional problems in the areas of security and management of data recovery.